The invention concerns a textile machine with a multiplicity of workstations, a central machine control and a machine bus for communication between the machine control and each, or possibly a group of electronic devices associated with each workstation, wherein a sensor device is located at each workstation.
A textile machine made known by EP 0 832 997 A2 possesses a multiplicity of workstations and respectively, a workstation electronic device is placed at each said workstation. The workstation electronic devices are respectively grouped with a section controller by a connection through a data interface. Section controllers are, in turn, interconnected by a data line to a machine bus. The machine bus is further connected to a machine center in such a manner, that the machine center controls the sectional controllers which are connected in parallel along the machine bus. This arrangement accordingly provides control for the workstation electronic devices. At each workstation electronic device a thread-monitor is located, which detects the presence of a thread at its assigned workstation and in a case of absence of a thread, transmits a corresponding signal to the workstation electronic device. The body of information transmitted from the thread-monitor, that is, the data throughput demanded for this purpose, is very small, since the information provided, i.e. “Thread Lacking”, for example, is only given out by a break in the running thread. This is an event which occurs but seldom.
In the case of a disclosed communication structure, namely from WO 85/01073, the workstations of a textile machine are monitored by respective warning instruments. In this way, the sensors are placed at each workstation and accordingly transmit analog thread-signals to a processor. Analog thread-signals from a group of monitoring sensors can be evaluated by one processor and subsequently transmitted in digital form through a communication channel to a communication processor. Several processors are connected in parallel onto the said communication channel. The data, which are transmitted from the processors to the communication channel, are received by a centralized unit of the thread monitoring system and are there evaluated.
From this centralized unit, in turn, alarm signals and commands for intervention are sent over a communication connection to a control center of the textile machine. Because of the thread-signal, the monitoring at the workstations requires a stand-alone communication structure.